Probing Nebular Physical Conditions Using the Hydrogen Recombination Spectrum Zhang, Y. ; Liu, X. -W. ; Wesson, R. ; Storey, P. J. ; Liu, Y. ; Danziger, I. J. Abstract Publication: Planetary Nebulae Beyond the Milky Way Pub Date: January 2006 DOI: 10.1007/3-540-34270-2_22 Bibcode: 2006pnbm.conf..183Z